At present, machines of small dimensions are used which maneuver in large numbers over the working area and which cut the product and bring it to a lorry or trailer parked at the side of the field. The small size of these machines means that they have to go backwards and forwards many times between the working area and the lorry or trailer, which has the double drawback of a loss of time and destruction of the product which remains on the field. The destruction of the remaining product is a particularly great drawback when, as is the case with spinach, it is harvested at two periods of the year, for example in the autumn and the spring. The abundance and quality of the second harvesting is dependent on the good condition of the product which remains on the field after the first harvesting.
Sometimes, in order to avoid these frequent backward and forward journeys, each of these small machines is accompanied by a tractor coupled to a trailer, which follows a parallel circuit at the same speed, in order to receive the product as it is gathered. The result of this is the doubling of the imprints on the ground, with, as an additional consequence, the destruction of the product which remains on the field.
In addition, the small harvesting machines used at present cannot operate in wet weather because they easily become stuck, all the more so in that their intensive journeyings rapidly transform the field into a quagmire, with the additional effect of accentuating the damaging effects on the product remaining in the field which have already been mentioned above.
This drawback, which is particularly serious if harvesting has to be carried out in the autumn when the ground is often wet, is particularly tiresome when the harvest must supply a processing system, for example, a canning industry, as the stoppage of the harvesting also stops the processing system making personnel idle.